Underfeed fire pot



Sept. 6, 1932.

J. MADLEHNER UNDERFEED FIRE POfI Filed April 13, 1929 INVENTOR di/afee ATTORNEY Patentedsept. s, 1932 I i l, 1,876,310-

UNITED STATES PATENTl oFFlcE" 'UNDERFEED FIRE POT Application led April 13; 1929. Serial No. 354,956.

The present invention relates to improveon the lower edges of the grate .sections 16.

n ments in an underfeed lire pot and relates The grate sections 1G extend from the upper particularly to the detail construction of the end of the fire pot 14 to Ajust above the upper fire pot used in my copending application end of the supporting member 6.

5 filed April 13, 1929, Serial No. 354,957' one Air forsupporting combustion in the grate 55` object of the invention being the provision is supplied by a blower (not shown) through of a lire pot in which the air 'feed orgrate the space between the pipes 8 and S and portion is `made`up of interlocking sections ythrough the space between the extensions and held in place by av retaining ring and 7 and 9 to the space 13 between the grate and 10 the base -portion of the pot in a desired flared the supporting member 6 and thence through .60' nd clamped 'position so that the sections the ribs 24 and perforations 25A to the inteiay ,be easily 4renewed when necessary. rior ofthe grate. l

Another objectof the present invention is A row of radial openings 11 is formed in' the provisionl of means by which airis supthecylindrical extension 9 ofthe ire pot 14 i l'plied to the combustible material in the ireimmediately behind the upper bend l2 be- 65 v pot but is prevented from causing a backa tween the fire pot 14 and the cylindrical exiir'e in the fuel delivery chute or conveyer. .tension 9 of the latter. Air issuing fromthe In the accompanying draw1ng:- space 10 through said openings will mix with Fig. l is a longitudinal Sectional View 0f any gas formed in the tire po1j'14 below the zo the complete fire pot; p grate and deliver such gas to the lower end 79 I `"nl grate, extends into the end of thecylindr/igalplurality of longitudinalgrooves are also 5J Fig. 2 is a top plan view of a portion of ofthe grate. Thus such gas as maybe formed thegrate 0r air supplying portion thereof; in the fuel as it is delivered to the re pot Fig. 3 is a perspective view of one 0f the will be prevented from passing back into and sections of the grate; through the fuel delivery pipe S and the Fig. 4 is a section taken on the line 4:.-4 possibility of such gas exploding in the fuel 75 of Fig. 1, showing the ends 0f a P2111' '0f rSGC- delivery pipe and setting ire to the fuel in the tions separated and latter willfbe avoided. Y

Fig; -5 is a section taken on the line 5--5J .The upper edge of each grate section 16` is of Fig. 1. shaped, as at 18, to fit into a shoulder 19 y I' The numeral 6 desgflil'svgenerally a Sup-` formed on the under side of an annulus 20 80 portingmember of substantially the Shape 0f whose inner circumference coincides with the an inverted truncated cone and has a tubular inner face 0f the grate- This annulus is pr0 extension 7 projecting rearwardly from itS vided withan apertured'rim engaging porlower portion, upon the end tif which the end tion 21 which rests. `upon the rim 14 of the'l E' of alpipe 8 is mounted. y outer casing 6 and is secured thereto by bolts e5 A fire p'ot 14,"mounted in the supportlng 22,/one only being shown .in the present ine member and spaced from thelatter by aperstance.V Thus the annulus 2O acts as aclalnptured webs 10a and 10", hasy axc'ylindrical exing ring to hold the lgrate sections 16 in place lSEIISOII 9 Projecting-rearwardly from its lowwithoutthe necessity of other bolts or fasten- 40 er portion into the tubular extension-7 o'f ings tolattach the sections to the member 14. 9C vthe supporting member. Y l, Each grate section 16, as clearly?illustrat-v f kA 'fuel supply pipe S, throughi'which fuel ed in Figs. 3 and-4, is provided with a pluis delivered by a screw conveyor to the/fire pot *rality of external transverse Areinforcing ribs 14 and thence-into the lower portion of the l23 and longitudinal reinforcing ribs 24; .A

extension 9. s f formed in the outer surface of each grate sec- The supporting member 6 extends above tion and la plurality of apertures 25 extend the u per 'end of the fire pot 14 and the upper from the bottoms of such grooves through the end o the fire port 14 is shouldered, as at 15', grate sections through which air passes from to engage complemental shoulders 17 formed the space 13 tothe grate. 1' L Each grate section 16 is provided, as best shown in Figure 4, with an angular portion 26 and projection 27 at one end and an inclined portion 28 and recess 29 at the-oppo-l site end, the `angular portion `9.6 and proj ect-ion 27 being complen'iental to the inclined portion and recess 29 so that the sections, when placed in position, interlock circumterentially and are held together by the i annulus 20.

From the foregoingdescription it is evident that after removal of the bolts 22 and the an nulus 2O any of the grate sections that arev Warped or burned. outfmay be readily renewed thus providing a very silnplefmeans of repair.

It is also apparent that, by'reason of the outlets l1, the gases of combustion are direct-r ed upwardly into the/'combustion zone and are prevented from entering the fuel as it is fed by the conveyer into the lower end of the fire pot, thus overcoming a fault that Vis pres-V ent in most underfeed burners and making the present burner exceedingly safe and practical.

I claim-as' my invention 1. An apparatus of the character described,

comprising a casing having its upper end 4open and surrounded by a flange, said easing having a tubular extension projecting rearwardly from its lower portion, a fire pot mounted in said casing and spaced therefrom, said fire pot having its upper end open and disposed below the upper end of said casing,

said lire pot also vhaving a lcylindrical eX- tension projecting rearwardly from its lower portion into and. spaced from the extension of said casing, a grate of substantially inverted truncated cone shape mounted in the upper open end of said casing and havingv its lower end supported by the open upper end of said re pot, and an annulus mounted `on the anged upperendof said casing and havinga recess in its under side in which the lupper end of said grate is seated.

2. An apparatus of the character described,

vcomprising a casing open at its upper endw and having a tubular extension projecting rearwardly from its lower portion, a vtire pot mounted in said casing and spaced therefrom with its upper end open and disposed below the upper end of said casing, said fire pot havwardly from its lower portion into 'and spaced from the extension of said casing, a grate of substantially inverted truncated -cone shapemounted in the upper -end of said casing and provided with perforationsin its wall, said grate having its lower end resting on the upper end of said fire pot, the,exten\ sion of said fire -pot having apertures in its wall rearwardly of the fire 'pot body for the admission of air from the spacebetween said tubular extensions to the re pot below the lower end of the grate'.4

3. An apparatus of the character described,

mg a cylindrical extension projecting reareral edges have portions eomplemental to and inter-fitting with the lateral edges of the adj aeent sections and the upper and lower edges of said sections being supported respectively by the upper ends of said casing and re potbut unattached thereto.

. In testimony whereof I4 have hereunto set my hand. f

JACOB MADLEHNEB.

v'les 

